Cornwall Mammal Group

Order: Carnivora, Cornish Names: Yewgenn, Ermin

In 2013 a stoat in full ermine was reported in North East Cornwall, a very unusual record, making this animal highly visible in the absence of snow!

Conservation:

Stoat populations are probably stable after declining since the 1950s, possibly associated initially with declining rabbit numbers and thereafter an increase in foxes. Stoats are listed in Appendix III of the Bern Convention. The stoat has no specific legal protection in the UK.

Recognition:

Although stoats occur across Cornwall they may beunder-recorded in many areas. They are absent fromthe Isles of Scilly. Stoats occur across Northern Europe and into Asia as well as in North America where it is known, confusingly, as the short-tailed weasel. The stoat was introduced into Australia and New Zealand in an unsuccessful attempt to control rabbit populations; it is now a significant pest species.

Records:

2007-2012: 421

2002-2007: 452

Pre-2001: 853

Total: 1726

Survey Methods:

No specific methods. Footprint traps and camera traps may provide some data. Most records from incidental sightings, cat kills and road casualties. The National Game Bag Census (Game and Wildlife Conservation Trust).

Although seldom seen, the stoat is probably
our most common carnivore. When glimpsed as it dashes from a roadside verge it moves in an almost snake-like manner with its long
body and short legs. At up to 440 mm long (a third of which is the black-tipped tail),
weighing up to 475 g, males are 50% larger
than females. The stoat has a sandy brown back and a cream belly, the margin being almost straight. In the autumn in northern latitudes the coat may change to white, keeping the black tail tip: this valuable ermine coat was used in the regalia of nobility. The colour change is controlled by temperature and snow cover rather than day length and in Cornwall the autumn moult, although paler than the summer coat, usually remains brown.

The stoat is a solitary and territorial animal found in a variety of habitats from lowland farms to high moorland. Males defend territories of up to 250 ha, the size of which depends on food availability and habitat type. During the breeding season the male’s territory may expand dramatically to cover more, smaller, female territories. When available, rabbits make up 50% of the stoat’s diet with birds, eggs, rodents, berries, and insects also taken. Stoats may kill full-grown rabbits several times their own size and are occasionally seen dragging their prey into cover. Stoats typically hunt along hedges, banks and woodland perimeters staying under cover. They are mainly active at night, but also hunt in daylight during the summer and will use several dens within their range.

Stoats mate during early summer but the implantation of the fertilised eggs is delayed until the following year and a litter of 6-13 kits is born in late spring. The kits are weaned by 5 weeks and disperse at 3 months. Many young females are mated before they leave the nest. In the wild few survive beyond 18 months although they can live to 10 years in captivity.

Stoats are regarded as significant predators of game birds and are still trapped and

shot by landowners. Historically, stoats were hunted for their winter coat, the ermine form. Other predators include foxes, dogs and cats, as well as birds of prey, although the pungent anal scent glands are strongly repellent to many predators. Many stoats die on roads, especially as they often hunt along verges, they may also die from secondary rodenticide poisoning. Many younger animals die from starvation, especially when myxomatosis affects rabbit populations. Infestations of the nematode worm, Skrjabingylus nasicola are often found in the nasal passages of stoats. It is possible that these infections may cause the ‘dancing’ behaviour seen in stoats where they fling themselves around in the open, although this was once thought to be an attempt by the stoat to mesmerise its prey.

Tracks and Trails:

In soft ground the stoat may leave tracks similar to the weasel and overlapping in
size range. The dark droppings, or scats, are deposited randomly and sometimes in the den. They are 40-80 mm long with characteristic twist. They may contain bones, fur and feathers and have a strong musty smell when fresh, which soon fades.

Did you know?:

The stoat moults twice a year. In the spring moulting starts at the head, progresses across the back and then to the underside. In the autumn, the moult is more rapid but starts on the belly and ends at the head. Unlike most carnivores, southern stoats tend be larger than their northern cousins - British stoats are larger than those of northern Europe, Russia or North America.